freebsd-nq/lib/libc/gen/dlfunc.c
Garrett Wollman dc12134a80 Reorganize dlfcn.h slightly to separate out XSI and BSD interfaces.
Add new dlfunc() interface, which is a version of dlsym() with a
return type that can be cast to a function pointer without turning
your computer into a frog.

Reviewed by:	freebsd-standards
2002-05-29 16:25:43 +00:00

31 lines
761 B
C

/*
* This source file is in the public domain.
* Garrett A. Wollman, 2002-05-28.
*
* $FreeBSD$
*/
#include <dlfcn.h>
/*
* Implement the dlfunc() interface, which behaves exactly the same as
* dlsym() except that it returns a function pointer instead of a data
* pointer. This can be used by applications to avoid compiler warnings
* about undefined behavior, and is intended as prior art for future
* POSIX standardization. This function requires that all pointer types
* have the same representation, which is true on all platforms FreeBSD
* runs on, but is not guaranteed by the C standard.
*/
__dlfunc_t
dlfunc(void *handle, const char *symbol)
{
union {
void *d;
__dlfunc_t f;
} rv;
rv.d = dlsym(handle, symbol);
return (rv.f);
}